LM1876 single power supply audio power amplifier circuit

As shown in the figure, this is the single-power supply audio power amplifier circuit of LM1876. The basic working principle of LM1876 single-power supply is the same as that of dual-power supply. The difference is that when single-power supply is used, 91kΩ resistor and 100kΩ resistor are used to divide the voltage to obtain about 1/2VCC as the bias voltage, which is added to the input terminal of LM1876 through Q1 voltage follower, so that the output voltage changes up and down with 1/2VCC as the reference, so the maximum dynamic range can be obtained. The "*" in the figure is an optional component, which is mainly used to suppress the high-frequency self-oscillation of the amplifier; if there is no high-frequency self-oscillation and the amplifier works stably, it is not necessary.